Patent GB-1094147-A (GB)
Title: Vigilance control system for use in vehicles such as locomotives
IPC: B60L3/02
Filed: 1965-11-23
Abstract: 1,094,147. Controlling locomotives. I. K. PURI. Nov. 23, 1965, No. 49643/65. Heading B7H. A vigilance control for a locomotive comprises an electrically-controlled mechanical, pneumatic or hydraulic timing device arranged to close two pairs of contacts 11, 12 and 13, 14 at respective ends of a timed cycle, one contact 11, 13 of each pair energizing a separate audio and/ or visual warning signal, and the other contact 12, 14 of each pair energizing a time-delay relay 18 which closes a switch 19, should a buttonoperated cancellation switch 40 not be actuated by the driver, to cut-off the traction power, bring the engine to idling condition and apply the train brakes. As shown the timing device comprises a pneumatic cylinder 1 containing a spring-loaded piston 3 connected to a rod 4 which actuates the contacts 11, 12 and 13, 14. Compressed air supplied to the cylinder 1 through an inlet 7 moves the piston 3 upwardly in the cylinder 1, firstly at a rate set by a needle valve 8 and subsequently, after the piston passes an air bleed to an auxiliary cylinder 62, at a rate reduced according to the setting of a needle valve 63. In a predetermined time the rod 4 closes the contacts 13, 14 whereupon a horn 15 and warning light 16 inform the driver that the cancellation switch 40 should be pressed before the time-delay relay 18 closes the switch 19. Magnetic valves 10, 64 are opened if the cancellation switch 40 is depressed to exhaust the cylinder 1 and auxiliary chamber 62 whereupon the spring 5 moves the piston downwardly until contacts 11, 12 are closed to energize the timedelay relay 18 and a warning light 17 indicating that the cancellation switch must be released so that the cycle can be repeated. Should the driver fail to actuate the cancellation switch, the time-delay relay 18 closes the switch 19 after a preset interval to energize a coil 30 which displaces a contact 46 in a switch 31 to open contacts 33 cutting-off the traction power and bringing the engine to idling condition, and to close contacts 34 energizing a brake valve 35 and audio-visual warnings 36, 37, the application of the brakes being recorded on a recorder 38. Traction power can then be restored and the brakes released by closing the cancellation switch 40, only if parallel throttle and reversing handle switches 41, 42 and 43, 44 duplicated on opposite sides of the cab are closed to complete a circuit between the switch 40 and a coil 39 which restores the contact 46 to its original position. Switches 49, 50 in parallel with the cancellation switch 40 reset the timing device whenever the throttle or whistle cock is actuated by an alert driver. A treadle switch in parallel with the switch 40 provides an alternative means of resetting the timing device, and may be temporarily isolated by a latching type switch. An over-speed control switch 51 energizes the time-delay relay 18 and provides an audio signal 52 if excessive speeding occurs. An automatic train control switch 53 closed upon approaching a stop signal provides an audio signal 55 and energizes the time-delay relay 18 to apply the brakes unless cancelled by a switch 54. A switch 24 is closed automatically whenever the engine is running to energize the vigilance device from a battery 20, but a switch 22 provides for rendering the device inoperative in all except the leading vehicle of a number operating in tandem. A switch 26 actuated by brake line pressure closes a magnetic valve 9 in the inlet to the cylinder 1 to suspend operation of the device when the driver is controlling the train by means of the brakes or when the vehicle is stopped with the brakes applied. Should the vigilance device fail to function correctly, an emergency isolating switch 33 may be operated after breaking a glass panel.